Characterization and mechanistic study on pancreatic lipase inhibitory effect of teas and their bioactive compounds

Pancreatic lipase (PL) plays a pivotal role in dietary lipid digestion. This study investigated the inhibitory effects of six tea types and their bioactive components against PL. Enzymatic assays revealed that white tea exhibited the strongest PL inhibitory effect, which was significantly affected by geographical origin, grade, and storage duration. An untargeted metabolomics approach, combined with a correlation analysis, identified catechins, dimeric catechins, organic acids, and phenolic acids as major components responsible for PL inhibition; this was validated by in vitro enzymatic assays. Mechanistic investigations involving fluorescence spectroscopy, circular dichroism, and molecular docking demonstrated that these compounds were bound near the PL active site, induced conformational changes in PL secondary structure, and led to non-competitive inhibition. Collectively, these findings elucidated the molecular mechanisms underlying the inhibitory effect of tea on PL and provided novel perspectives on the role of tea in regulating dietary fat digestion.